1. Field of the Invention
The present invention relates to a position controller for an optical element which can be moved to correct image shake and removed to a position outside an anti-shake driving range of the optical element.
2. Description of the Related Art
There has been an increasing number of optical devices such as cameras which are equipped with an anti-shake mechanism (image shake correcting mechanism/image stabilizing mechanism) that moves a specific optical element such as a lens element or an image sensor (image pickup device) in a plane orthogonal to an optical axis of an optical system to reduce (correct) image shake. In Japanese Unexamined Patent Publication 2007-101993, a technique for removing (radially retracting) an image-stabilizing optical element to a position outside an anti-shake driving range (to a position off an optical axis of the optical system) when an optical device that incorporates the anti-shake mechanism moves from an operating state to a lens barrel accommodated state (fully retracted state/non-operating state) in which no pictures are taken, has been proposed for the purpose of making a lens barrel compact in size.
In order to miniaturize such an optical device, a mechanism for removing the image-stabilizing optical element to a removed position away from an optical axis also needs to be miniaturized. In the lens barrel disclosed in the aforementioned Japanese Unexamined Patent Publication, a driven member which is driven in a plane substantially orthogonal to an optical axis to correct image shake is provided thereon with a rotatable frame which holds a lens element (image-stabilizing optical element), and the rotatable frame is rotated to move the lens element to a removed position away from the optical axis with the driven member fixed at the center of the anti-shake driving range thereof (i.e., centered thereon) when the lens barrel is brought into the lens barrel accommodated state (fully retracted state). According to this structure, the amount of rotation of the rotatable frame corresponds to the removing amount of the lens element; however, if the amount of rotation of the rotatable frame is great, the driven member that holds the rotatable frame becomes great in size or the shape of the driven member becomes complicated. Therefore, it is desirable that the amount of rotation of the rotatable frame be reduced as small as possible to achieve miniaturization of the image-stabilizing optical element removing mechanism, specifically in radial directions from the optical axis.